Respiratory System 2008-2009

Why do we need a respiratory system? _____________________ ___________________ ______________ food ATP O2 CO2

_________________ Lungs ______________ ________

Lungs Structure spongy texture ______________ moist lining high surface area more absorption of O2 ______________ small air sacs moist lining mucus traps dust, pollen, particles covered by cilia hair-like extensions of cells move mucus upward to clear out lungs

Moving gases into bloodstream Inhale ______________ ______________ ______________ Exhale _________________

Gas exchange: Diffusion of gases Gases move by diffusion from high to low concentration capillaries are thin-walled tubes of circulatory system alveoli are thin-walled sacs of respiratory system capillaries in lungs capillaries in muscle O2 O2 O2 O2 CO2 CO2 CO2 CO2 blood lungs blood body

Negative pressure breathing ___________________ moves down & expands chest cavity pulls air into lungs inhale exhale

Automatic Brain Control You don’t have to think to breathe! ________________ ________________ ________________ medulla & pons measure blood pH CO2 = pH (acid) coordinate breathing, heart rate & body’s need for energy

Breathing and Homeostasis ATP Homeostasis keeping the internal environment of the body balanced ___________________________________ Exercise __________________________ need more ATP bring in more O2 & remove more CO2 Disease need to work harder to bring in O2 & remove CO2 CO2 O2

Gills: getting O2 out of water Gills are gas exchange membranes outside of the body thin tissue high surface area must stay wet lots of blood vessels __________________ ___________________ water gills Just keep swimming…

You can breathe now, and… Ask Questions!! 2008-2009